Copernicus ranks 2025 as world's third-warmest year on record

Copernicus climate data published after the end of 2025 ranked the year as the third warmest in the global instrumental record, behind 2024 and 2023. The annual average remained far above the nineteenth-century pre-industrial reference used in international climate assessment.

Rankings depend on dataset methods, geographic coverage and later data updates, so other major scientific agencies can report small differences while agreeing on the long-term warming trend. A few hundredths of a degree between annual ranks is less important than the persistent elevation across recent years.

Human-caused greenhouse-gas emissions are the principal driver of long-term global warming. Natural variability, including ocean conditions and volcanic or aerosol influences, affects the order of individual years. One annual rank is not a direct measure of every local weather event.

The Paris Agreement's temperature goals concern long-term warming, not a single calendar year crossing a threshold. Nevertheless, repeated annual anomalies increase evidence that the climate is approaching or exceeding dangerous levels without rapid emissions reductions.

The annual climate entry uses the completed annual assessment rather than inventing a precise result before the dataset closed. It attributes the ranking to Copernicus and preserves methodological scope. Regional heat, storms and impacts require their own observations and cannot all be inferred from a global mean.

Copernicus combined billions of observations with numerical reanalysis to produce a globally complete estimate. Reanalysis is a scientific method that assimilates measurements into a model, not a substitute invented where no observations exist.